This invention relates to certain novel trisubstituted 3,5-difluoropyridines, to the preparation of such compounds, to herbicidal compositions containing such compounds, and to a method of combating undesired plant growth using such compounds.
Pyridines and their derivatives have many uses in the pharmaceutical area as well as in agriculture (herbicides, fungicides, acaricides, anthelmintics, bird repellents), as reagents, intermediates and chemicals for the polymer and textile industry.
The broad generic formula of the International patent application WO 96/06096 embraces fluorinated 2-azolyl-5-aryloxypyridines.
Similar 2-aryl-5-aryloxypyridines are disclosed by EP 0 723 960. The co-pending U.S. patent application Ser. No. 08/680,193 (Case 33,272) discloses 2-thienyl-5-aryloxypyridines. However, there is no hint to 3,5-difluoropyridines in any of these documents.
The co-pending U.S. patent application Ser. No. 08/688,591 (Case 33,273) discloses 2,6-bisaryloxy-3,5-difluoropyridines.
Although many of the known compounds show considerable activity against various weeds, they are not completely satisfying with regard to their selectivity or because of their persistence.
The compounds according to the present invention combine high herbicidal activity with the necessary selectivity and enhanced soil degradation.